Perimenopause Symptoms and Irregular Periods: What Counts, What's a Red Flag, and the 34-Symptom List

Irregular periods in perimenopause have a published definition. The staging criteria clinicians use, the full symptom list, and the bleeding to get checked.

Perimenopause has a formal definition, and it's built on your cycle rather than your age or your symptoms. A group of researchers convened by the National Institutes of Health, the North American Menopause Society, the American Society for Reproductive Medicine, the International Menopause Society and the Endocrine Society published it as the Stages of Reproductive Aging Workshop, known as STRAW+10. Here is the line that matters:

You have entered early perimenopause when the length of consecutive cycles differs persistently by seven days or more. Persistently means it happens again within ten cycles.

A 28-day cycle followed by a 36-day cycle, and then it happens again a few months later. That's the criterion. Not hot flashes, not an FSH result, not your age.

Late perimenopause starts when you skip a period for 60 days or more. From there, the average time to your final period is short. Menopause itself is diagnosed backward: twelve consecutive months with no bleeding at all.

That's what perimenopausal means, and knowing it changes what you can say in an appointment. "I think I might be perimenopausal" gets a shrug. "My cycles have gone from 28 days to 37 and back twice in the last eight months, which meets the STRAW criteria for the early transition" gets a different conversation.

I'm a medical technologist, not a physician. What follows is the staging criteria, the symptom list with the ones that get missed, the bleeding patterns that need a doctor rather than a wait-and-see, and where testosterone fits into a picture that's usually described as an estrogen story.

The stages, in plain terms

Late reproductive stage. Cycles still regular. FSH rising and becoming more variable. This is where a lot of women first notice something is different without anything measurable to point at.

Early perimenopause (STRAW stage -2). Cycle length varies persistently by seven days or more. FSH is elevated but variable in the early follicular phase, and AMH and antral follicle count are low.

Late perimenopause (STRAW stage -1). Skipped cycles, with amenorrhea of 60 days or longer. Hormone levels swing to extremes, and cycles increasingly happen without ovulation. FSH above 25 IU/L on a random draw is characteristic of this stage.

Postmenopause. Twelve months after your final period, which you can only identify in hindsight.

The whole transition runs a median of about four years, with a range that stretches from a few months to about ten. That length is the single most useful thing to know, because it explains why "you're too young for menopause" is a poor answer at 44. You very likely are too young for menopause. You are not too young for perimenopause.

Why one FSH test tells you almost nothing. In the late transition, STRAW notes that FSH is sometimes elevated into the menopausal range and sometimes sits squarely in the range of your reproductive years, particularly when estradiol is running high. Draw the blood on a good week and it looks normal. Draw it a fortnight later and it doesn't. A single FSH result in a woman who is still bleeding cannot rule perimenopause in or out, and if you've been reassured on the strength of one, that's the reason it didn't match how you feel.

Irregular periods: what's ordinary and what isn't

Cycle changes in perimenopause come in a few recognizable patterns, and most are expected.

Cycles getting shorter first. Many women notice periods arriving every 24 or 25 days before they ever start getting longer. That's a normal early pattern.

Cycles getting longer, then variable. The seven-day swing that defines the early transition. Often it alternates: short, long, short, long.

Skipped periods. Two months, then a period, then three months. This is the late transition, and the erratic bleeding that follows a long gap is often heavy, because the lining has had longer to build.

Heavier or lighter flow. Both happen. Anovulatory cycles produce unopposed estrogen effects on the lining, which is why the heavy months tend to arrive after skipped ones.

What is not ordinary, and needs an appointment rather than a wait:

Bleeding between periods. Common in perimenopause and still worth investigating, because polyps, fibroids and endometrial changes present the same way and the only way to distinguish them is to look.
Bleeding after sex. Always worth checking.
Very heavy bleeding. Soaking through a pad or tampon every hour or two, passing clots larger than a quarter, or flooding through protection.
Cycles consistently shorter than 24 days.
Periods lasting longer than seven days, or bleeding that goes on for weeks.
Any bleeding at all after twelve months with no periods. Postmenopausal bleeding is never dismissed and is always investigated.

Most of these turn out to be benign. The point of getting them looked at is that "it's just perimenopause" and "it's a polyp" and the small number of things that are more serious all feel identical from the inside, and the investigation is usually an ultrasound and a conversation.

The 34 symptoms question, and the ones that get missed

You'll see "the 34 symptoms of perimenopause" everywhere. The number circulates widely online, and no medical body publishes an authoritative list of exactly 34 items; different versions of the list contain different things. The symptoms themselves are real and documented. The tidy number is a piece of internet folklore.

What's worth having is a grouped list, because the surprising entries are the ones that lead women to five specialists instead of one.

The ones you were told about: hot flashes, night sweats, irregular periods, vaginal dryness, low libido, sleep disruption, mood swings.

Musculoskeletal, and badly underrated. A 2026 systematic review and meta-analysis of 37 studies covering 93,021 women found perimenopausal women have an increased risk of muscle and joint pain compared with premenopausal women. Within that literature, one study of women presenting with shoulder pain found synovitis significantly more common in perimenopausal women (25.1%) than premenopausal women (6.2%). That's the finding worth knowing. Frozen shoulder turned up often in both groups in the same study, 35% of the perimenopausal women and 32% of the premenopausal ones, and that difference was not statistically significant, so it isn't evidence of a hormonal link by itself. If you're 47 and your shoulder has seized up for no reason, shoulder trouble at this stage of life is a well-documented pattern, and hardly anyone connects it to hormones on the first visit.

Headaches and migraine. Estrogen withdrawal is a migraine trigger, and perimenopause is a decade of repeated withdrawal. A 2026 review in the Journal of Headache and Pain describes migraine and menopause as converging factors in brain vulnerability, notes that abrupt estrogen withdrawal (as in surgical menopause) can precipitate acute worsening, and reports that roughly one-third of women continue to have migraine beyond menopause. New headaches in your forties, or old migraines suddenly getting worse and less predictable, belong on the perimenopause list.

Mood and mental health. This is the one where women get the most inappropriate treatment. Perimenopause carries an elevated risk of depression and anxiety, and the symptoms cluster with everything else rather than arriving alone. In a 2024 survey of 5,744 women by Newson Health (a private UK menopause clinic, so treat it as what women report rather than as clinical evidence), 95% described a negative change in mood since their symptoms began, about one in five had been formally diagnosed with a mood disorder, and 39% (2,213 women) were offered an antidepressant instead of HRT as first-line treatment. In that same survey, close to one in five women needed more than six appointments or investigations before anyone attributed their symptoms to changing hormones.

Cognitive. Forgetting words mid-sentence, losing the thread in meetings, walking into rooms. It's real, it's measurable, and it has its own page: menopause brain fog.

Everything else that gets its own specialist. Palpitations. Tinnitus. Dry eyes. Itchy skin and formication (the sensation of something crawling on your skin). Burning mouth. New or worsening allergies. Digestive changes and bloating. Recurrent urinary tract infections and urinary urgency. Dizziness. Body odor changing. Nails splitting. Hair thinning at the crown while showing up on your chin.

The reason this list matters is not to alarm you. It's that each of these on its own leads somewhere else: the cardiologist for the palpitations, the ENT for the tinnitus, the gastroenterologist for the bloating, the dermatologist for the itching. Seen together in a woman between 40 and 55 whose cycles have started to wander, they have a common cause, and one appointment could replace four.

Where testosterone fits into this

Almost every perimenopause resource describes the transition as an estrogen story with progesterone as a supporting character. Your ovaries also make testosterone, and you make more of it than estrogen by mass. How much more moves around a lot: roughly even at the estradiol peak of an ovulatory cycle, and fifteen times or more after menopause, once estradiol has fallen away and testosterone hasn't.

The testosterone curve doesn't match the estrogen curve at all. Testosterone declines gradually with age rather than dropping at menopause: by around 40 it's roughly half what it was in your early twenties, and it falls another quarter or so from your early forties into your late fifties, reaching its lowest point around 58 or 59 before rising modestly again. That decline starts years before your cycles change.

Which means a woman in her early forties with regular periods, a normal FSH and a flat, unmotivated, low-libido, foggy version of herself is not describing an impossible thing. She may be describing the part of this transition that begins first and gets measured last. That argument, with the neuroscience behind it, is here: low testosterone in women over 40, drive and ambition.

Two honest caveats. Testosterone's only formally evidence-based indication is low sexual desire with distress, and on mood the 2019 global consensus is blunter than most people quoting it let on: available data do not show an effect of testosterone on depressed mood (Level I, Grade B), and show no effect on general wellbeing (Level I, Grade A). Those are null results at the highest level of evidence, not gaps waiting to be filled. Cognition is the outcome that sits in the insufficient-evidence column, and it's the only one. My own mood lifted on testosterone and I'll keep telling you that, but it's one woman's experience running ahead of the trials, not what the guideline found. And for most perimenopausal women, getting estradiol right is the intervention that changes the most, with testosterone added afterward if something is still missing. Order matters: testosterone dosing for women covers where it goes in the sequence.

What to do with all this

Track your cycles for six months. Dates, length, flow, and one line about how you felt. This is the single most useful thing you can bring to an appointment, because it turns "my periods have been weird" into data that meets or doesn't meet a published criterion.

Write your symptoms down as a list, not as a story. The pattern is the diagnosis. Told one at a time across four appointments, they look like four unrelated complaints.

Don't accept a single FSH as an answer while you're still bleeding. Ask what it would mean if it were drawn two weeks later.

Get the red-flag bleeding looked at, even while you're being told the rest is normal.

Ask about treatment, not just confirmation. A diagnosis without a plan is a wasted appointment. Hormone therapy, local vaginal estrogen, sleep, resistance training and (for some women) testosterone are all on the table, and which ones fit depends on your history.

If you're being offered an antidepressant for symptoms that started when your cycles changed, it's fair to ask whether hormone therapy has been considered and why it was ruled out. Antidepressants have a real place, including in my own life for 30 years. They belong in the conversation as one option rather than as the default answer to a hormonal change.

Questions I get asked

What does perimenopausal mean? The transition into menopause, defined by cycle changes rather than by age. It begins when consecutive cycle lengths differ persistently by seven days or more, and ends twelve months after your last period. The median length is about four years, though it can run anywhere from a few months to about ten.

Can you be in perimenopause with regular periods? The formal staging says the transition begins with cycle variability. Symptoms very often start in the late reproductive stage before cycles change, and testosterone in particular has usually been falling for years by then. So you can absolutely feel perimenopausal before you meet the cycle criterion, and it's worth saying it that way rather than being told you can't be.

Is it normal to skip periods in perimenopause? Yes. Amenorrhea of 60 days or more defines the late transition. What's still worth checking is heavy or unpredictable bleeding when a period does arrive after a long gap, and any bleeding once you've gone twelve full months without one.

Why do I have bleeding between periods in perimenopause? Anovulatory cycles and fluctuating estrogen are the usual explanation, and polyps and fibroids are common at this age too. Since you can't tell them apart by how it feels, intermenstrual bleeding gets investigated rather than assumed.

Are perimenopause headaches a real thing? Yes. Estrogen withdrawal triggers migraine, and perimenopause delivers repeated withdrawals. New headaches or worsening migraine in your forties deserve to be discussed as part of the hormonal picture rather than treated in isolation.

How long does perimenopause last? A median of about four years, ending twelve months after your final period, with a range that runs from a few months to about ten. There's no way to know in advance where you'll fall in it.

Should I get my hormones tested? For confirming perimenopause while you're still cycling, a hormone panel usually adds less than your cycle diary does, because the levels swing so much. Testing is useful for other reasons: ruling out thyroid disease, checking ferritin if you're bleeding heavily, and establishing a baseline testosterone and SHBG if testosterone therapy is on the table.

If you take one thing from this page, make it the seven-day rule. It's a specific, published criterion that you can apply to your own calendar tonight, and it converts a vague suspicion into something a clinician has to engage with.

I'm a medical technologist sharing my own reading of the research and my own experience of this transition, not your doctor. Take any of it to someone who can examine you and read your labs alongside it.

The other pillars on this site: testosterone dosing for women · low sex drive in perimenopause · menopause brain fog

Sources

Staging and cycle criteria - Harlow SD, Gass M, Hall JE et al., Menopause 2012, Executive summary of the Stages of Reproductive Aging Workshop + 10: source for the persistent seven-day cycle-length difference defining early transition, the recurrence-within-ten-cycles rule, the 60-day amenorrhea criterion for late transition, the FSH above 25 IU/L characterization, and the observation that FSH in late transition sometimes sits within the reproductive range.

Musculoskeletal symptoms - Kruse C, McKechnie T et al., JBJS Open Access 2026, Musculoskeletal Manifestations of Perimenopause: a systematic review and meta-analysis of 37 studies and 93,021 women, finding increased risk of muscle and joint pain in perimenopause. The shoulder figures come from a single study within that review, in 197 perimenopausal and 113 premenopausal women: synovitis 25.1% versus 6.2%, which was significant, and adhesive capsulitis 35% versus 32%, which was not.

Headache and migraine - Gazerani P, The Journal of Headache and Pain 2026, Migraine and menopause as converging factors in brain vulnerability: source for estrogen withdrawal as a trigger, the effect of abrupt withdrawal in surgical menopause, and the finding that approximately one-third of women continue to experience migraine beyond menopause.

What women report - Newson Health, Women's Experiences of Perimenopause and Menopause 2024, a self-published survey of 5,744 respondents. Not peer reviewed, published by a private menopause clinic with a commercial interest, and cited here only for what women say about their own care: the 95% reporting a negative mood change, roughly one in five formally diagnosed with a mood disorder, the 39% (2,213 women) offered an antidepressant instead of HRT as first-line treatment, and the proportion needing more than six appointments before their symptoms were attributed to hormones.

Testosterone in the picture - Davis SR, Baber R, Panay N et al., J Clin Endocrinol Metab 2019, the Global Consensus Position Statement on the Use of Testosterone Therapy for Women: the single evidence-based indication, the finding of no effect on depressed mood (Level I, Grade B) and no effect on general wellbeing (Level I, Grade A), and the classification of cognitive outcomes as insufficiently evidenced. - Davis SR and Wahlin-Jacobson S, Lancet Diabetes and Endocrinology 2015: source for women's circulating testosterone concentrations being high relative to estradiol. It supports the direction only, not a fixed multiplier. - Zumoff B, Strain GW, Miller LK, Rosner W, J Clin Endocrinol Metab 1995: the origin of the "about half by 40" figure, an expected 0.61 nmol/L at 40 against 1.3 nmol/L at 21. Read off a fitted regression in 33 healthy cycling women, so treat it as a well-replicated shape rather than a precise measurement. - Wang Y, Islam RM, Bond M, Davis SR, eBioMedicine 2025, the Australian Women's Midlife Years (AMY) study, 1,104 women aged 40 to 69 measured by mass spectrometry: median testosterone fell from 0.56 nmol/L at ages 40 to 44 to 0.42 nmol/L at 55 to 59, roughly a quarter, reaching a nadir at 58 to 59 before rising modestly, with no effect of natural menopause itself.

The red-flag bleeding list above reflects standard gynecological practice rather than a single paper, and it is deliberately conservative. Any of those patterns is a reason to be seen, not a diagnosis.